Save in-progress keysat integration and StartOS 0.4 work

Snapshot of the working tree before cleanup. Captures:
- Keysat licensing: server/license.js, /api/license/* endpoints in
  server/index.js, activation modal in public/index.html, embedded
  Ed25519 issuer key (assets/issuer.pub).
- StartOS 0.4 expansion: setApiKey action, version files v0.1.1
  through v0.1.15, file-models/config.json.ts, manifest updates.
- Self-hosted registry server (startos-registry/).
- Build/deploy scripts (bin/bump-version.sh, bin/deploy.sh, vendored
  yt-dlp binary), .gitignore, .deploy.env.example.
- Recent design docs (KEYSAT_INTEGRATION.md, UPGRADE-DESIGN.md) —
  retained here so they remain recoverable when removed in the
  follow-up cleanup commit.

startos-registry/node_modules/safer-buffer/dangerous.js

@@ -0,0 +1,58 @@
+/* eslint-disable node/no-deprecated-api */
+
+'use strict'
+
+var buffer = require('buffer')
+var Buffer = buffer.Buffer
+var safer = require('./safer.js')
+var Safer = safer.Buffer
+
+var dangerous = {}
+
+var key
+
+for (key in safer) {
+  if (!safer.hasOwnProperty(key)) continue
+  dangerous[key] = safer[key]
+}
+
+var Dangereous = dangerous.Buffer = {}
+
+// Copy Safer API
+for (key in Safer) {
+  if (!Safer.hasOwnProperty(key)) continue
+  Dangereous[key] = Safer[key]
+}
+
+// Copy those missing unsafe methods, if they are present
+for (key in Buffer) {
+  if (!Buffer.hasOwnProperty(key)) continue
+  if (Dangereous.hasOwnProperty(key)) continue
+  Dangereous[key] = Buffer[key]
+}
+
+if (!Dangereous.allocUnsafe) {
+  Dangereous.allocUnsafe = function (size) {
+    if (typeof size !== 'number') {
+      throw new TypeError('The "size" argument must be of type number. Received type ' + typeof size)
+    }
+    if (size < 0 || size >= 2 * (1 << 30)) {
+      throw new RangeError('The value "' + size + '" is invalid for option "size"')
+    }
+    return Buffer(size)
+  }
+}
+
+if (!Dangereous.allocUnsafeSlow) {
+  Dangereous.allocUnsafeSlow = function (size) {
+    if (typeof size !== 'number') {
+      throw new TypeError('The "size" argument must be of type number. Received type ' + typeof size)
+    }
+    if (size < 0 || size >= 2 * (1 << 30)) {
+      throw new RangeError('The value "' + size + '" is invalid for option "size"')
+    }
+    return buffer.SlowBuffer(size)
+  }
+}
+
+module.exports = dangerous